A permanent magnet motor represents a type of motor where a fixed stator causes rotation of a movable rotor. The rotor typically includes multiple magnets embedded in or connected to the rotor, and the stator typically includes multiple conductive windings. Electrical signals through the windings generate a rotating magnetic field that interacts with the magnets of the rotor, causing the rotor to rotate.
“Sensorless” motor control refers to an approach where one or more characteristics of a motor, such as motor speed or rotor position, are mathematically derived. Sensorless motor control typically avoids the use of separate speed and position sensors that are mechanically attached to a motor, which might otherwise detrimentally affect the performance of the motor (such as by affecting the maximum torque output per volume and drive system reliability).